The Wall Street Journal reports this morning that carbon emissions in the US have fallen 12 percent since 2005, a sharp drop that has many energy policy experts surprised. The reason? The replacement of coal-fired electricity with power gained from natural gas. While natural gas is carbon-based too, it is much cleaner-burning:

Last year, 30% of power in the U.S. came from burning natural gas, up from 19% in 2005, driven by drilling technologies that have unlocked large and inexpensive new supplies of the fuel.

The U.S. trend hasn’t led to a global decline in carbon emissions, which increased 15% from 2005 through 2011, according to federal statistics. An International Energy Agency report this week concluded that China’s rising reliance on coal to fuel economic growth jeopardizes progress toward what the IEA calls “a low-carbon future.” But the U.S., which has decreased its carbon-dioxide output tonnage more than any other nation, demonstrates that market forces can have an impact on greenhouse gases even as politicians continue to disagree over what, if any, federal regulations are needed to force industries to reduce their emissions.

White House spokesman Clark Stevens said important progress had been made reducing emissions and the federal government was committed to implementing standards that “help ensure that we remain on a path to reduce these emissions.”

U.S. carbon-dioxide output rose steadily in the 1990s and 2000s, peaking in 2007. In 2008, the economy weakened and power generation from natural gas and renewables began to increase, a combination that led to a sharp reduction in emissions. The Energy Department, which had been expecting increasing emissions, began lowering its forecasts in 2009. It now says carbon-dioxide emissions will begin rising year-on-year in 2015 but won’t return to 2005 levels through 2040.

The new drilling technology for unlocking the natural gas reserves? It is called “fracking.” Environmentalists have been attacking it, arguing it is dangerous to ground water among other things. Despite these claims, there is only specious evidence that that is the case.

The administration has been touting natural gas as a “bridge fuel” to a renewable future, although they have been cautious in making that move. Nevertheless, the use of natural gas has been a boon towards the White House’s efforts to reduce carbon emissions, the Journal reports:

The decline in U.S. emissions from 2005 to 2012—706 million metric tons of carbon dioxide—puts the U.S. a long way toward achieving the 17% reduction in greenhouse-gas emissions from 2005 the Obama administration set as its 2020 goal a few years ago.